Comments made on social media have been detrimental to an investigation into the fatal stabbing of a Levin man, police say.

Ambulance and police staff found Michael Les Valentine, 27, on the front lawn outside his home on an unnamed gravel road off State Highway 1, 7 kilometres north of Levin, on Friday night.

Detective Senior Sergeant Marc Hercock said preliminary results from an autopsy completed today revealed Valentine died from a single stab wound to his chest likely caused by a knife. No other major injuries were identified, Hercock said.

A 31-year-old man is scheduled to appear in the Palmerston North District Court tomorrow charged with murder.

Two other men, aged 22 and 29 have been charged with assault. Comments made on social media had been detrimental to the police investigation soaking up resources that could have been used elsewhere, he said.

“The comments on social media are not consistent with what we know.

“We are only 48-hours into this investigation and there are still a number of lines of inquiry to follow, not to mention collation of evidence.

“I want to make it clear that at no stage have police said that the three men arrested were friends of Mr Valentine's. We have spoken to all the witnesses we believe to have been at the scene at the time of the stabbing. They have provided us with information that gave us the lines of inquiry to locate the three offenders.

“The 15 staff deployed on this investigation are working incredibly hard to respond to any information we receive. When information can’t be validated such as some of the claims on social media, these impede the progress we are making.’’

He appealed for sightings of a 1997 a white Mitsubishi Pajero 4WD, registration CTJ418, between the hours of 6pm to midnight on Friday.